Creating a Session for Snowpark Scala (original) (raw)

To use Snowpark in your application, you need to create a session. For convenience in writing code, you can also import the names of packages and objects.

Importing Names from Packages and Objects for Snowpark¶

The Snowpark API provides a number of classes, objects, and functions that are available in different packages. For convenience, you can import the class, object, and function names from packages and objects to avoid having to use qualified names.

For example:

• The com.snowflake.snowpark package contains the main classes for the Snowpark API. To import the names in this package, use:
  import com.snowflake.snowpark._
• The com.snowflake.snowpark.functions object defines utility functions (includingsystem-defined functions). To import the function names from this object, use:
  import com.snowflake.snowpark.functions._
• The com.snowflake.snowpark.types package defines classes and objects that you can use to define schemas for semi-structured data.
  import com.snowflake.snowpark.types._

Note

If you used the run.sh script to start the Scala REPL, the script already imports namescom.snowflake.snowpark and com.snowflake.snowpark.functions.

Creating a Session for Snowpark¶

The first step in using the library is establishing a session with the Snowflake database. To create a session, use theSessionBuilder object. You can access the SessionBuilder object through the builder field in theSession companion object:

import com.snowflake.snowpark._

... // Get a SessionBuilder object. val builder = Session.builder

To provide the details to establish a session with a Snowflake database (for example, the account identifier, user name, etc.), either create a properties file (a text file) or programmatically build a Map containing the properties.

In the properties file or Map, set the following properties:

• URL: Set this to the URL for your account in the form https://_accountidentifier_.snowflakecomputing.com.
  See Account identifiers.
  If the account identifier contains underscores (_), replace those underscores with hyphens (-).
• Any additional JDBC parameters (see JDBC Driver connection parameter reference in the JDBC driver documentation) needed to connect to Snowflake (e.g. USER, ROLE, WAREHOUSE, DB, SCHEMA, etc.).
• (Optional) snowpark_request_timeout_in_seconds: Set this to the maximum number of seconds that the Snowpark library should wait in the following cases:
  • Waiting for dependencies to be uploaded to a stage.
  • Waiting for an asynchronous action to complete.
    The default value of this property is 86400 seconds (1 day).
    Note
    This property was introduced in Snowpark 0.10.0.

To authenticate, you can use the same mechanisms that the JDBC Driver supports. For example, you can use:

• password-based authentication (by setting the PASSWORD property)
• key-pair authentication
• single sign-on (SSO)

For key-pair authentication, you can either:

• Set the PRIVATE_KEY_FILE property to the path to the private key file.
  If the private key is encrypted, set the PRIVATE_KEY_FILE_PWD property to the passphrase for decrypting the key.
• Set the PRIVATEKEY property to the string value of the unencrypted private key from the private key file. (If the private key is encrypted, you must decrypt the key before setting it as the value of the PRIVATEKEY property.)

To create the session:

1. Set the properties in the Session.builder object.
   • If you created a properties file, pass the path to the properties file to the Session.builder.configFile method.
   • If you programmatically built a Map of the properties, pass the Map to theSession.builder.configs method.
     Both methods return a builder object that has these properties.
2. Call the create method of the builder object to establish the session.

The following is an example of a properties file that sets the basic parameters for connecting to a Snowflake database. The example is set up to use key-pair authentication. Set PRIVATE_KEY_FILE to the path to the private key file. In addition, if the private key is encrypted, you must set PRIVATE_KEY_FILE_PWD to the passphrase for decrypting the private key:

profile.properties file (a text file)

URL = https://.snowflakecomputing.com USER = PRIVATE_KEY_FILE = </path/to/private_key_file.p8> PRIVATE_KEY_FILE_PWD = <if the private key is encrypted, set this to the passphrase for decrypting the key> ROLE = WAREHOUSE = DB = SCHEMA =

As an alternative, you can set the PRIVATEKEY property to the unencrypted private key from the private key file.

profile.properties file (a text file)

URL = https://.snowflakecomputing.com USER = PRIVATEKEY = ROLE = WAREHOUSE = DB = SCHEMA =

The following example uses this properties file to create a new session:

// Create a new session, using the connection properties // specified in a file. val session = Session.builder.configFile("/path/to/properties/file").create

The following example uses a Map to set the properties:

// Create a new session, using the connection properties // specified in a Map. val session = Session.builder.configs(Map( "URL" -> "https://.snowflakecomputing.com", "USER" -> "", "PRIVATE_KEY_FILE" -> "</path/to/private_key_file.p8>", "PRIVATE_KEY_FILE_PWD" -> "<if the private key is encrypted, set this to the passphrase for decrypting the key>", "ROLE" -> "", "WAREHOUSE" -> "", "DB" -> "", "SCHEMA" -> "" )).create

Closing a Session¶

If you no longer need to use a session for executing queries and you want to cancel any queries that are currently running, callclose method of the Session object. For example:

// Close the session, cancelling any queries that are currently running, and // preventing the use of this Session object for performing any subsequent queries. session.close();